Multiple speed transmission



Nov. 1, 1932. w. ROBERTS 1,885185'7 MULTIPLE SPEED TRANSMISSION' Filed May 3l, 1950 2 Sheets-Sheet l INVETOR. WILLmM ROBERTS ATTORNEYS.

NOV. 1, 1932. I W ROBERTS 1,885,857

MULTIPLE SPEED TRANSMISSION Filed May 31, 1950 2 Sheets-Sheet 2 n f A 4 ATTORNEYS Patented Nov. 1, 1932 UNITED STATES f WILLIAM ROBERTS, OF OAKLAND, CALIFORNIA vMiiixrirnn sensi) ritansnissroiv Application filed May 31, 1930. Serial No. 458,661.-

This vinvention relates Vto multiple speed transmissions or selective gear speed reducing systems'which provide forvarious speeds in a driven shaft from a constant speed driving shaft or vice versa. v y

The objects of the invention are to provide a compactmechanism of the type mentioned which will be adapted for direct Vconpling to a motor, willbe entirely enclosed, the driven or power delivery shaftwillbein axial alignment with the driving shaft, Vthe,

various speed gears may be engaged with the load without shock, noise or stopping the mechanism, the release of each gear will be positively effected, the action will be foolk proof, the selection of the speeds may be acf complished by simple operation of a handle which may project from the device at any desired angle', and the propery oiling of the gearsand bearings willV at all times be assured. w i y In the drawings accompanying this appli# cation, Figui is central section of'my multiple speed transmission showing the aligned driving and driven shafts and the arrange-v ments of gears and clutches within the casing and the view is taken as along the line l1 of Fig. 2. 'l

Fig. 2 is an end Vview of the transmission with a portion of the front` cover plate broken away to reveal the'meclianism within, and with a portion ofthe operating han dleshown insection.' 1 c Fig. 3 is a reduced size cross section taken along the line 3:-3 of Fig. l showing the interniediateK or `idler gears of the system. I Fig. i is-a diagrammatic view of an. op# tional hook-up for theA different speed gears.

Before'enteringi a detailed description of my improved multiple speed transmission it may be. briefly described as a casingenclosing .the ends of' the: aligned driving and driven shafts anda plurality 'of engaged gears arranged around the shafts on small shafts,lthe small shafts arranged in a circle about the lmain shafts, and each provided with afriction clutch, the friction clutches being operated selectively by means of`a rotatable arm :operated by a: cranlrfrom outside The `particular features vof the invention consist in thel arrangementof gears into two layers only, their -particular mounting, symmetrical arrangement, ability -tof run in `either direction without change :of adjustment, relation of the clutches and means of actuation, individual adjustment of the clutches from outside of the casing, positive release of each clutch, adjustability to vari'- ous positions of the clutchV operator,indica tor for various speeds`,and accessibility of the interior parts. Other featuresof minor importance will appear in thedetailed description to follow. Y i

En the drawings thecasing comprises a circular frame portion l Vprovided with bolt# ing feet or legs 2, and a circular pan-shaped cover/portion 3 secured tothe frame portion by cap'v screws 4 evenly'spaced around the margin so that the cover Ymay be lsecured in place-at any desired angle of rotation. Y The rear side of the frameportion is pro# vided with a flange 5 for 'bolting direct to a motor V(not shown)` if desired, by means of bolts 6. Itbeing understood that this iange will take any required shape or diameter' to suit the motor frame to which thetransmission is to be connected. lt should also be noted thatsince the transmission is usually heavier than 'themotor to which it couples, that the motor need not have supporting feet of its own as the assem# bla-ge inayjbe 'carried wholly npon'tlie feet of the transmission. Y

Centrally at opposite points on the rearof frame portion l and cover portion 3 ofthe casing are bosses 7, 7 supporting within packing ringr and bearingsv indicated andthrough which bosses and bearings respectivelyfextend alignedl driving 8 and driven 9 shafts.

Shaft 8 is usually the shaft of an electric motor, through of Vcourse it may be any other power shaft,fwhile shaft 9 is the driven shaft whichmay be run at various speeds depends;

ing on the number and varietyof ygears used Il? in the system, and this depending merely'on the size of the casing. In practice aboutfour changes of speed are found sufiicient to l'ineet most requirements;

Within the casing and secured to the end of motor shaft 8 is a driving spur pinion 10 meshing with a larO'e spur gear 11.V This large lgear 11 is positioned between a pair of supporting rings 12 and 13 which fit within finished shoulders 14 on the casing and are spaced apart by means of bushings 15 on spacer pins 16 held securely kin position by suitable means such as the" set screws 17 These spacer pins project slightly into the frame 1 to prevent bodily turning of the rings, and both rings are held in position byV margin of cover 3 forced against them.

Gear 11 is one of four different size driven gears each mounted onshort clutch shafts 18. In Fig. 1 two only of thesegears are shown, 11 and 2O, but in Fig. 3 the four are shownunder numbers 11, 19, 20 and 21, being respectively, 1st or low speed, 2nd, 3rd,*a'nd 4th or highest speed. These gears are geared together by means-of spur idler gears 22, 23, 24 also carried between the rings 12 and 13 on pins 25 surrounded with bushings 26. The pins aresecured in place Aby set screws 25 Y The ends of theV clutch shafts 18-,as here shown have bearing support in ring 12 through meansV of solid (bronze) bushings 27 'pinned to the shafts, but are supported in ring 13 in ball bearings 28, the outer races of which are retained'against lateral shift' ing by means of thin sides of ring13. r- Y Clutch shafts 18 are slightly enlarged to the right of ring 13 and carryV male friction clutch members free to lrevolve on the shafts but each 'held-against longitudinal movement by inner'race ofthe ball bearing 28 and a shoulder 31, while secured to the hub of each clutch member 30 is a spur gear'32 meshing with a spur gear33 keyed to shaftv 9.

plates 29 on opposite The extreme inner endof shaft 9 is supported in a ball bearing 34 mounted ina of ring 13.

Clutch member 3() is in the form'of adoucentral bore ble cone at its outer end andl adaptedl to en-V gage complementarily formed clutch mem,- ber 35 slidably mounted or feathered to the outer end ofthe clutch shaft, so that upon engaging the clutch sections of any one clutch power will be transmitted from its driven geargto shaft 9. j y

The female member 35 of each clutch is normallyurged outward by means of a spiral compression spring 36 seated within a bore inthe clutch lshaft and bearing at its outer end against a small yoke 37 around Va 'pin 38V extending transverselyV ofthe clutch shaft through a slot 39 formed therein, and the pin projecting at its ends slightly` into a hole 40' drilledV transversely throug'hfthe fe` male clutch niembenfl rIhis arrangement confines the clutch member uponj the end of4 theclutch shaft but gives it free limited slfding movement for engaging and disengaging clutch member 30.

For applying engaging pressure to each clutch I provide the following construction: A- bearing 41 is counter-sunk into the outer end of each clutch member 35 and arranged with its inner race freeV of longitudinal obstruction and providedjwith a central stud orV button 42.withV an arched head having a slight depression in its outer end as indicated in dotted line, while directly opposite this button and threaded through a hole in the casing cover3 is asimilar stud and button 43. The outer end of the stud is slotted as at 44 to receive a screw driver and is provided with a lock nut 45 to lock it in adjusted position'. Y

This construction is repeated for each clutch and a revolving arm 46 provided with spring steel spreader ends 47 is rotatably mounted on shaft 9 so that its ends may be selectively brought between any .pair vof .buttons to resiliently force them apart... The ends of the spring spreader members 47 are rounded (as best shown in Fig. `2) so that they will wedge in between the rounding buttons 42, 43. Arm 46 has ahub-48 feathered withtapered jaws53 adapted whenthe disk is turned, towedge underthe inner shoulder of clutch members 35'and forcibly release lthem from clutching engagement with members 30. .The jaws 53 precede and follow arm 46-47 so that as soon asthe arniis-shifted from between a pair of buttons the clutch will be positively released'regardless of which .direction the arm is revolved.

YTo swing the arm in itscircular pathfor selectively-engaging the clutches I `provide a radially extending shaft 54, supported ina bearing boss 55 formedon casing cover 3, and carrying at its inner end va bevel pinion'o meshing with gear 5 0 and at its outer'end outside of the casing a crank handlei57.;rv

Crank handle 57 isy provided with a tubular hub 58 freely slidable over shaft 54'and provided with a transverse slot at its inner end engaging a drive pin 59 projectingfrom the Shaft, while Va `compression springGO reacting against a shoulder in thefhub and a retainer'plate 61 normally holdsy the crank engaged with the pin but permits axial dis'- engaging so as to provide for'operating the Vhandle at any desired sector of its revolution *This pin 59 is formedv at its ends toperiod- A ically advance an indexing gear or disk 62 on a bushing 49 loose'on shaft 9 and on whichV bushing issecured a bevel gear v50 and alsolak 'lio ' le'velindicator and filling plug 66.

Y sure buttons.

in place so that it may if desired also function as an oil plug, while at thebottom of the cas* ing is a laterally extending oil pipe 64 provided with a drain plug and a-combined A breather hole is provided in plug v63 by'drilling transverse and vertical connecting holes 69-70. C v

A feature which shouldbe mentioned is the provision o-f a-detent for the revolvable clutch arm at the `points of neutrality, that is, centrally'between each pairV of buttons 43 when the' clutches are disengaged. To carry out this I simplyrproviwde intermediate buttons the same in `all respects las 43 on the. cover 3 at points'midway between the clutch pres- Tlie studs of these intermediate buttons are designated 44 on Fig. 2 of the drawings.

While I have shown my improved transmission as including spur gear idlers to transmit power between the various clutch shafts,

it is evident that a silent or other form of power chain may connect them instead of the idlers, as indicated at 67 in Fig. 4.

As it is desirable in shifting speeds in a device of this kind that one proceed gradually through the dierent speeds I sometimes provide a stop for the rotating arm so that it can not pass directly from high to lowest speed clutch. Such a stop is indicated in Fig. 1 by the pin 68.

Having thus described my improved multiple speed transmission I may state that I am aware of other attempts'to arrange such gears in a circular row for selective engagement but such prior Varrangements have for various reasons not met with success and my invention represents important improvements over such earlier devices in the features above particularly described and hereinafter claimed.

I claim Y l. In a multiple speed gear transmission, a casing, driving and drivenshafts extending therefrom, change speed gears within the casi ing arranged for transmitting power between the shafts, a circular row of axially slidable clutches associated with said gears, and a rotatable device provided with means for resiliently forcing said clutches selectively into enga ement.

' 2. .In a multiple speed gear transmission, a casing, driving and driven shafts extending therefrom, change speed gears within the casing arranged for transmitting power between the shafts, a circular row of axially slidable clutches associated with said gears, and a rotatable spring arm arranged to successively bear against said clutches when the arm is lrevolved for forcing said clutches one at a time into engagement for transmitting power between said shafts.

3. In a'multiple speed gear transmission, a casing, driving 'and .driven Vshafts extending therefrom, change speed gears within .the

casing arranged for transmitting powerbetween the shafts,v` a'circular row of axially slidable clutches associated with said gears,

arotatable device provided with means forV resiliently forcing said clutches selectively into engagement, and means for individually adjusting the working pressure kof said clutches.

4. In a multiple speed gear transmission,

a casing, driving and driven shafts extending therefrom, change speed gears within the casing arranged for transmitting power between the shafts, a circularrowof axiallyslidable clutchesassociated with said gears, a rotatable spring arm arranged tovsuccessively bear against said clutches when the arm is revolved for forcing ysaid clutches vone at a'time into engagement for transmitting power between said shafts,` and means for separately adjusting the effective pressure Vof said spring arm on'the diiferentclutches.

5. In a multiple speed gear transmission, a casing, driving andxdriven shafts extending therefrom, change speed gears within the casing arrangedforftransmitting power between the shafts, a circular row of-axially slidable clutchesV associated. with said gears, a rotatable spring arm'arranged to successively'bear against said clutches when the arm .is revolved for forcing said clutches one at a time any ofv severalpositions around said casing.v

i 7; In a Vgear transmission of they character described including a casing, a shaft', a` clutch y.gear `thereon including an axially movable member f'or-engaginnr the clutch, and a spring arm reacting betweenV the casing and said member forengaging said clutch.

. 8; `In a gear transmission vof the character Vdescribed including a casing, a shaft, aclutch gear thereon -including an'r'axially movable member'for 'engaging the clutch,fa spring iis 'arinV reacting between the kcasing and said `memherfor engaging' said clutch, and-means for adjustingthe tension 'of said arniifrom without thevcasing. f, 9.. Ina gear transmission of the character vdescribed including a casing,- a shaft, aclutc'h gear thereon including a slidable clutch member at'the end of-said shaft, meansretaining said member upon said shaft, al spring tending toforce said member outward for disenvgaging said clutch, and means reacting between the outer 'end of said member and said casing for'forcngsaid clutch member inward for engagingfsaid clutch. l .v

10: In va gear. transmission ofy thecharacterdescribed including a casing,,a shaft,a

-clutch gear `thereon including a slidable clutch member at the end of said shaft, means Y retaining saidy member-upon saidshaft, a

Vof dissimilar size driven gears,

spring tendingto force said member outward for disengagingsaid clutch, av pressure boss carried by said clutch, a pressureboss carried lby said casing,1and spring means arranged to be interposed bet'weenthe bosses for resiliently forcing said-'bosses apart. i' 1 .11. In amultiple'speeditransmission, a circularc'asing, drivingand driven shafts extending therefrom, a'plurality of gears within the casing arranged for transmission of power ffromshaft to shaft, anda pairl of spaced rings in said casing supporting said gears. whereby said gears may be assembled on said ring-islandinserted: as .a unit in said casing, said gears-including .a circular row a-gear on said driving shaft meshingwith one vofsaid ldriven gears, and intermediate idler Ygears carried by said rings*connectingv said driven gears.` 1y i i l2. In a multiple speed transmission, a circular casing, driving .and drivenshafts extending therefrom, awplural-ity vof gears within the easing arranged for transmission of power from shaftfto shaft, a pair of spaced rings yin vsaid Vcasing supporting said Y gears whereby said gears may -beassembled on said ringsand inserted as annit in saidreasing, said gears including a ,circular row of dis'- similar sizedrivenlgears, a gear onsaid driving shaft meshing :with one of said driven gears, and intermediate'dler gearscarried by said rings.connectingsaidf-driven gears, shafts entendingthroughfsaidrings and on which' said driven gears are mounted, clutches a5 'gear' on said driven shaft meshing with said clutch gears,` and means V for `selective'lyfen-v gaging said clutches.

Y respectively.

at its`inner end meshing with the gear -of saidarm. Y, p 'I 14. In a construction as specified in claim 12, said means for, engaging said clutches comprisingV an arm mounted forvrotation said arm is attached, anioperating shaftextending "out of said casingcarrying a gear at its inner .end meshing with the gear of said arm, and an indicatorv showing the rela-` form size-spur vgears supported around said' shaft inv-mesh with said spur gear, and gear means for imparting various speeds fromthe other shaft to the gears of said circular row "if wrLLiAM Roiiasntrs.

Von-'said shafts, clutch `gears on said clutches, i i

l3. In a construction as specified inclaim i i 12, said meansforfengaging said clutches comprising an arm mounted ,for rotation around said driven shaft, ai gear to which :'saidjarm isattached, andan, operating shaft extending'put of said casing carrying afgear around said driven shaft, a gear toiwhich 

